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排序方式: 共有410条查询结果,搜索用时 11 毫秒
51.
Reduced endothelial progenitor cells in European and South Asian men with atherosclerosis 总被引:4,自引:0,他引:4
Hughes AD Coady E Raynor S Mayet J Wright AR Shore AC Kooner JS Thom SA Chaturvedi N 《European journal of clinical investigation》2007,37(1):35-41
BACKGROUND: Circulating endothelial progenitor cells (EPCs) play a role in the repair and regeneration of the endothelium and may represent a novel cardiovascular risk factor. South Asian subjects have an increased risk of cardiovascular disease which is not fully explained by known risk factors. This study examined associations of EPCs with atherosclerosis and possible ethnic differences in EPCs. MATERIALS AND METHODS: A population sample of 58 European and South Asian adult men was enriched with the recruitment of an additional 59 European and South Asian men with known coronary disease. The coronary artery calcification score was measured by multi-slice computerized tomography (CT), carotid and femoral intima-media thickness (IMT), and femoral plaques were measured by ultrasound. The subjects were further subdivided into three categories of coronary artery disease on the basis of coronary artery calcification score and clinical history. Total EPCs and non-senescent EPCs (ns-EPCs) were quantified after 5 days cell culture and the number of late outgrowth colonies was measured over a 6-week test period. Circulating CD34+ haematopoietic precursor cells were measured by flow cytometry. RESULTS: Individuals with femoral plaques had reduced total and ns-EPCs. The number of ns-EPCs were reduced in individuals with the most coronary atheroma and were inversely related to the coronary calcification score and femoral IMT. These relationships persisted after multivariate adjustment for other risk factors. The numbers of late outgrowth colonies or circulating CD34+ cells were unrelated to the presence of atherosclerosis. There were no differences in the number of EPCs between European and South Asian subjects. CONCLUSION: The number of EPCs are reduced in subjects with atherosclerosis independent of other risk factors. Reduction in EPC numbers may be an independent risk factor for atherosclerosis but does not explain ethnic differences in cardiovascular risk. 相似文献
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The Big Bang theory, a widely accepted theory of the origin of the universe, states that the universe was created between ten to twenty billion years ago from a cosmic explosion. Charles Darwin, a 19th century English naturalist, convinced the scientific community through his work that life evolved by natural selection over three and a half million years ago rather than through the influence of a Supreme Being or creator. Although there has been scientific data to support the claims of natural selection, there still remain many unanswered questions suggesting that other mechanisms contributed to the evolution of life. These unresolved findings greatly influenced mysticism and the development of the theological argument, which suggest the existence of a supreme being (God), who is believe to be an omnipotent healer, comforter, provider of salvation, and the center of mysticism spirituality. There has been consistent use of spiritual practices to address health concerns by individuals for thousands of years. There is increasing data that supports the implementation of spirituality in nursing for client care to enhance health outcome and patient wellbeing. Incorporating spiritual care into practice is an integral dimension of holistic care that is the crux of nursing practice in the 21st century. Holistic care of clients requires that nurses use the nursing process to implement spiritual care in practice. 相似文献
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Joanna Buscemi Tiffany M. Rybak Kristoffer S. Berlin James G. Murphy Hollie A. Raynor 《Journal of behavioral medicine》2017,40(4):565-573
The purpose of this study was to explore relations between food craving, caloric intake, and body mass index (BMI) changes over the course of an 18-month weight loss trial. Two-hundred two obese adults (mean BMI = 34.9 kg/m2; mean age = 51.30 years, 92.2% White; 57.8% female) who participated in a behavioral weight loss trial completed measures of food craving, caloric intake, and BMI at baseline, 6 and 18 months. From baseline to 6 months, higher initial food cravings were associated with more gradual and less steep reductions in BMI. Additionally, the relation between changes in food craving and BMI changes varied by levels of change in caloric intake, such that BMI change and change in food cravings were positively associated at low levels of change in caloric intake, but were unrelated at average and high levels of change in caloric intake. Similarly, from baseline to 6 months and from 6 to 18 months, the relation between changes in food craving and BMI changes also varied by initial levels of caloric intake. Explicit clinical targeting of food craving management may be beneficial for individuals beginning weight loss programs, especially for those who report higher levels of food craving at baseline. Baseline caloric intake and change in calorie intake over time may serve as moderators of the relation between food cravings and BMI. 相似文献
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Raynor PC Cebula JI Spangenberger JS Olson BA Dasch JM D'Arcy JB 《Journal of occupational and environmental hygiene》2012,9(1):1-13
This study was conducted to determine if engineered nanoparticles are released into the air when nanocomposite parts are shredded for recycling. Test plaques made from polypropylene resin reinforced with either montmorillonite nanoclay or talc and from the same resin with no reinforcing material were shredded by a granulator inside a test apparatus. As the plaques were shredded, an ultrafine condensation particle counter; a diffusion charger; a photometer; an electrical mobility analyzer; and an optical particle counter measured number, lung-deposited surface area, and mass concentrations and size distributions by number in real-time. Overall, the particle levels produced were both stable and lower than found in some occupational environments. Although the lowest particle concentrations were observed when the talc-filled plaques were shredded, fewer nanoparticles were generated from the nanocomposite plaques than when the plain resin plaques were shredded. For example, the average particle number concentrations measured using the ultrafine condensation particle counter were 1300 particles/cm(3) for the talc-reinforced resin, 4280 particles/cm(3) for the nanoclay-reinforced resin, and 12,600 particles/cm(3) for the plain resin. Similarly, the average alveolar-deposited particle surface area concentrations measured using the diffusion charger were 4.0 μm(2)/cm(3) for the talc-reinforced resin, 8.5 μm(2)/cm(3) for the nanoclay-reinforced resin, and 26 μm(2)/cm(3) for the plain resin. For all three materials, count median diameters were near 10 nm during tests, which is smaller than should be found from the reinforcing materials. These findings suggest that recycling of nanoclay-reinforced plastics does not have a strong potential to generate more airborne nanoparticles than recycling of conventional plastics. 相似文献
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Desmocollins form a distinct subset of the cadherin family of cell adhesion molecules. 总被引:13,自引:2,他引:13 下载免费PDF全文
S Mechanic K Raynor J E Hill P Cowin 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(10):4476-4480
The desmosomal adhesive core is formed by four major components: desmoglein (Mr, 165,000), desmocollins I and II (Mr, 120,000 and 110,000, respectively), and a Mr 22,000 protein. Here, we report the cloning and sequencing of cDNAs encoding a bovine desmocollin. The open reading frame found in the longest cDNA, 5 kilobases, contains a region encoding a protein of 839 amino acids. The features of the deduced amino acid sequence imply that the mature 707-amino acid desmocollin is a type I transmembrane protein that is produced by proteolytic cleavage of an 810-amino acid precursor. The ectodomain of desmocollin contains repeats that show extensive sequence similarity to members of the cadherin family of calcium-dependent cell adhesion molecules. A comparison of the amino acid sequences of desmocollin, desmoglein, and the cadherins shows that although these intercellular junctional adhesion molecules share a consensus sequence in their adhesive domains that defines them as a family, several features, including the divergence in the sequence of their cytoplasmic tails, divide them into three distinct subtypes. 相似文献
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